206 Blades Leading edge

[WLM]

Hi

We have a B206II which came from the UK in late 2005. As the transmission is having maintenance, I had the chance to get a good look at the leading edge on both blades. they have 2400 hrs to run but about 1/4 of the leading ledge from the outer end looks like something out of Swiss cheese... Since joining that company, I have been asking them to wash the blades on a regular basis and after each overwater flights, but it's a fight all the times

Now how safe is it to have so many small holes in the leading edge? local engineers maintain it's within published Bell 206 limits....

Thanks
WLM

[Gomer Pylot]

It's safe enough, but you will lose some lift due to the roughness. How much is hard to say, but having the leading edges smoothed seems to help a little. Flying through rain really roughens them. Water isn't that hard, but when the drops hit at near the speed of sound, they can do some damage, and will quickly roughen the leading edge. The metal is thick enough that the roughness isn't dangerous, but having someone who knows what he's doing take a file to it may be worthwhile.

[WLM]

Thank you Gomer P.
I remember using a protective tape on KH4 blades to prevent erosion/damage. Only problem the tapes used to come off after a while, whistling, ect etc. Most of the time we would take them off as it would put the track/balance out. BUT the blades leading edges did look better.
Any thought on it? and are the tapes still available?
Cheers
WLM

[Gordy]

Blade tape is still available in the US. I used it all the time on the 206 and the Astar. Like you say--it does start to peel after about 20 hours----just pull it off and replace. (If you pull it off one blade---be sure to pull it off the others at the same time to avoid problems).

[WLM]

Thanks Gordy
Any link or contact please for the Blade Tape?
Cheers
WLM

[360andoutofhere]

Try 3M tape-P/N 8663-6. HSI in the US stock it. It is pretty durable stuff and will last more than 20 hours.

[RVDT]

Applying blade tape to any of the above aircraft, unless it is in the maintenance manual, or there is an STC to cover it, is ILLEGAL.

Any incident resulting from same practice would have your insurers looking askance I am sure.

:=

[ericferret]

Blade tape is legal for the 206 and always has been.

Without it, in the European wet climate the blades will struggle to make TBO.
The rub is that the tape is expensive and doesn't last long.

We used to tape from new and stop at about 2/3 blade life. No point in putting tape on a blade that is heading for the scrap bin.

Not sure what the Bell 206 MOM says it about it these days but we used to apply tape in one foot sections over the prescribed length.

There were two benefits, firstly if a section split it was easier to replace and secondly the loss of a section had little effect on the flight characteristics.

Bell recommened putting on one long strip several feet long. Great fun when it started to peel off in one big piece.

The MOM limits are large and if the engineers are saying it's within limits then I am sure that is true. Could be the blades are not far off their scrap life.

Trying to tape a badly erroded blade is difficult and often not successful.

[360andoutofhere]

You can smooth off the leading edge with a small grinding pad on a drill (you'll be amazed how much the MM allows) and then apply the tape. It will adhere a lot better to the smooth surface.

[quichemech]

When you need a new set of blades, there is an STC available to put stainless edges on the blade, it's just a capping strip but does work quite well. If your machine flies lots of hours then it maybe worth it.

[500e]

This may help
http://products3.3m.com/catalog/us/en001/government/innovative_solutions/node_2DPN88V7Z5be/root_GS3RBW6QFVgv/vroot_31S2JJ7584ge/gvel_2FVF67HB1Vgl/theme_us_innovativesolutions_3_0/command_AbcPageHandler/output_htm

3M8672 polytape 4".
We are getting far in excess of 80 hours life, read instructions
Make sure blade is clean, free from polish, and flaking paint, warming tape & blade (leave in sun for a time)helps the bond.